The Respiratory System Flashcards
The lungs are located in the _
Thoracic cavity
air enters the respiratory tract through the the external _ where it is filtered by mucous membranes and nasal hairs called _
nares
vibrissae
What keeps food out of the respiratory tract
the opening in the larynx called the glottis, which is covered by the epiglottis.
from the larynx where does air go
into the trachea and then into one of the two mainstem bronchi
the bronchi divide into smaller structures known as _
bronchioles
where does gas exchange occur
alveoli
Why are alveoli coated with surfactant
its a detergent that lowers surface tension and prevents the alveolus from collapsing.
What membranes surround each lung
the pleurae
What is the intrapleural space and its importance
the space within the pleural sac which contains a thin layer of fluid. pressure differentials here ultimately drive breathing.
what are the external intercostal muscles
layer of muscles between the ribs that expands the thoracic cavity.
Explain the intrathoracic volume and intrapleural pressure when the diaphragm contracts and relaxes.
relaxed= decreased volume; increased intrapleural pressure contracted= increased volume; decreased intrapleural pressure
What tool is used to measure lung capacities and volumes
spirometer
What is total lung capacity (TLC)
the maximum volume of air in the lungs when one inhales completely
What is residual volume (RV)
the volume of air remaining in the lungs when one exhales completely
What is Vital capacity (VC)
the difference between the minimum and maximum volume of air in the lungs (TLC-RV)
What is Tidal volume (TV)
the volume of air inhaled or exhaled in a normal breath
What is expiratory reserve volume (ERV)
the volume of additional air that can be forcibly exhaled after a normal exhalation
What is inspiratory reserve volume (IRV)
the volume of additional air that can be forcibly inhaled after a normal inhalation
How is breathing regulated
regulated by a collection of neurons in the medulla oblongata called the ventilation center. These neurons contain chemoreceptors that are primarily sensitive to CO2.
As the partial pressure of carbon dioxide in the blood rises the respiratory rate will _
increase
hypoxemia describes
low oxygen concentration in the blood
The capillaries bring deoxygenated blood from the _; loaction
pulmonary arteries; which originate from the right ventricle of the heart.
what is the driving force for gas exchange
the pressure differential of the gases
Explain vasoconstriction and vasodilation in regard to thermoregulation
vasoconstriction = conserves thermal energy vasodilation= dissipates thermal energy
The nasal cavity contains _ which attacks the _ walls of gram-_ bacteria
lysozyme
peptidoglycan walls
gram positive
The lungs contain _ which engulf and digest pathogens
macrophages
what is the importance of mast cells
populate the lungs; have preformed antibodies on their surfaces and release inflammatory chemicals to promote an immune response
What is the bicarbonate buffer system
CO2 + H2O -> H2CO3 -> H+ + HCO3 (reversible)
an increasing hydrogen ion concentration will cause a shift in the bicarbonate buffer system resulting in _
the generation of additional carbon dioxide and will promote an increase in respiratory rate
Describe the relationship between hydrogen ion concentration and pH
when pH is lower = higher H+ concentration
when pH is higher = lower H+ concentration
What is the effect of scar tissue formation in the alveolar walls
decreased inspiratory reserve volume
What is the effect of an excess of fluids within an entire lobe of the lung
no diffusion will occur in the affected area
What do infants lack in their respiratory system
surfactant
